Timing mechanism



y 25, 1933- v L. CHENAULT 1,920,003

TIMING MECHANISM Filed Jan. 14. 1932 9% R03 L. dkerpapwi.

Patented July 2 5, 1933 UNITED STATES PATENT OFFICE ROY L. OHENA'ULT,

MENTS, '10 GULF RESEARCH OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR, BY MESNE ASSIGN &; DEVELOPMENT CORPORATION, OF PITTSBURGH,

PENNSYLVANIA, A CORPORATION OF DELAWARE TIMING MECHANISM Application filed January 14, 1932. Serial No. 586,685..

This invention relates to timing mechanismwhich is actuated by fluid pressure from a continuous source of supply for alternately connecting and disconnecting two or more ports through which fluid under pressure flows for the actuation of devices with which such timing mechanism is associated, and more particularly the invention comprises a fluid actuated valve which embodies a dumb-bell type piston reciprocable from end to end of a chamber under the influence of the pressure of accumulated fluid exerted,

on the ends of such piston, with detent means for holding the piston at either extremity of its stroke until sufiicient pressure has accumulated to move it to the other extremity of its stroke, and ports controlled by the piston in its movement to alternately establish and out ofl communication between the source of fluid pressure and the mechanism to be operated by the intermittent application of such pressure; all as will be described more fully hereinafter, and as claimed.

In the accompanying drawing illustrating several forms of a specific embodiment of my invention;

Fig. 1 shows, partly diagrammatically and partly in cross section, the timing mechanism applied to the intermittent actuation of a valve in a pipe line; i

Fig. 2 is a sectional view partly in section and partly in elevation and shows an arrangement for controlling the flow of liquid to two different pointsof use; and

Fig. 3 is a segmental detailed view partly in section and partly in elevation showing an arrangement for operatingasmall mechanical device such as counter or the like.

The invention may be used for supplying a liquid or gas to apparatus at any desired time intervals, for supplying different chemicals in definite proportionsto a valve or mixing chamber, and for many other uses which it is needless -to here enumerate.

It will be evident from the following description that the timing may be adjusted to close limits and that an infinite number of timing combinations are possible for the reason that the time the piston of the valve remains in one position of its stroke is wholly independent of the time it remains in its other position.

Referring more particularly to the drawmg:

A pipe which has connection with a source of fluid under pressure (not shown) terminates in a four-way union 11 from which branch pipes 12, 13, and 14: extend to convey the pressure fluid to reservoirs 15 and 16, and to cylinder 17 within-which a dumb-bell. type piston 18 is slidably retained. The piston comprises enlarged heads 19 and 20 connected by a\ portion 21 of reduced diameter to afford a space within the cylinder and between the heads. This space is in effect a portedchamber, varying in position but not in size. I

piston heads 19 and Either or both of the 20 are 'formed with a pair of annular grooves 22, 23, 24, 25, into one of which a detent 26 is yieldingly pressed by a spring 27, compressed by the screw 28 which is threaded into the tubular extension 29 of cylinder 17. Obviously, the detent mechanism may be duplicated for cooperation with both heads of the piston simultaneously.

The reservoirs or pressure chambers 15 and 16 have outlets 30 and 31, respectively,

communicating with the cylinder 17 at its ends, and in the inlets 12 and 14 are regulatmg valves 32 and 33 which ma be independently adjusted to regulate t e flow of pressure fluid into the respective reservoirs" or chambers.

The valve cylinder 17 has vent ports 34 and 35 one of which is opened upon each stroke of the piston to alternately relieve the reservoirs 15 and 16 of pressure. Thus, when valves 32 and 33 are set to admit fluid to the reservoirs 15 and 16 at the-desired rate, the accumulation of fluid in chamber 15 will overcome the inertia of the piston and at a predetermined pressure, will overcome the holding eifect of detent 26 whereupon the piston-will move from the position shown in the drawing to its other extreme position in which it closes vent 35and opens vent 34 for the relief of pressure in chamber 15 while at the same time pressure is being may be position of the with a gear 45' of a counting device or the llke, as'

' closed by piston right permitting chamber 15 built up in chamber 16. Upon movement of the piston to the right as seen in the draw-.

ing the detent 26 will engage in groove 24 and will thus prevent return movement of the piston until; the sufficient and predetermined presure has been built up in reservoir 16f Timing of the piston in its reciprocation regulated not only by adjustment 'of valves 32 and 33, but also by the capacity of the reservoirs used. Thusit is seen that the piston may be made to reciprocate rapidly or slowly and with or without regularity.

If it is desired to operate small mechanical contrivances by the reciprocation of thev the piston may be provided with a piston, rod 42 extending through packin g gland 43 in an end wall of the cylinder an provided rack 44 for engagement with a inion shown in Fig. 3.

In the form of invention illustrated, a pipe 36 is tapped into the cylinder 17 to communicate with the space around the reduced portion of the piston, and in the piston shown this space is pipe 37, the inlet 13 being head 20.

Pipe 36 leads into a housing 38 which contains a diaphragm operating upon the application of ressure'to depress a valve stem 39 and there y to actuate the valve in pipe line 40. p A coiled spring 41 holds the valve stem in contact with the diaphragm at all also vented by a times.

paratus to be in the position shown in the rawing, air or'gas under pressure from the source of Assuming the parts of the-a suppl passes through pipe 1.0 and .into bran pipes 12, '13, and 14. Since the end of pipe 13 is closed by piston head 20 the pressure fluid will not ast valves 32 and 33, which have been crac ed open the desired extent, and into reservoirs 15 and 16. From the reservoir 16 the fluid escapes through pipe 31 into the end of cylinder 17 from which it passes by way of vent pipe 35, but the fluid in reservoir 15 flows into pipe 30 and exerts its pressure upon the end of cylinder head 19.

when the pressure in chamber 15 hasbeen built up sufliciently to overcome the friction of piston 18 and. the holding effect of the detent 26, the piston valve will slide to the to vent to the atmosphere through the end of the cylinder and pipe 34 while at the same time pressure commences to build up in reservoir 16. The pipe 13 being no longer closed, fluid under pressure will enter the space between the piston heads and by flowing into pipe 36 will exert pressure on the diaphragm in housing 38 to actuate the valve or other mechanism. When the piston again returns to its initial position, the vent pipe 37 is comprising a source enter cylinder 17 but uncovered to relieve the cylinder 17 and pipe 36 of pressure and, thus, permit return of the diaphragm to normal position.

In one use of the mechanism for controlling the flow of liquids (see Fig.2) pipe 36 may be connected to a source of liquid and may communicate through the valve cylinder 17 with outlets 13 and 37. 'In such a structure the inlet 10 will be connected to branch conduits 12 and 14 by a T fitting and will not communicate with branch 13 as in the form of invention shown.

It will be understood that in the modified apparatus the flow of li uid from pipe 36 to outlets 13 and 37 is regu ated and controlled by movement of the valve 21 in its alternate movement from one end of the cylinder to the other. Flow is directed alternately to outlets 13 and 37.

If desired, the in Fig. 2 may also be used different liquids to a single predetermined intervals. y be accomplished by simply connecting pipes 13- and 37 to the source of supply of the liquids and connecting pipe 36 to the point of use.

. From the foregoing it 'will be apparent that this invention provides a simple and expedient timing mechanism which in its operation is independent of the apparatus which it controls inthat its action is not affected by conditions within the apparatus, and moreover that inithis invention the timto, supply two point of use at ing may be regular or irregular at the will 1.

of the operator. What I claim as my invention is: 1. A. pneumatically of fluid under pressure,

a cylinder and piston slidable therein, pressure reservoirs having outlets communicating with said cylinder at its end portions and inlets communicating with said source of fluid, valves in said inlets for regulating the flow of fluid into the respective reservoirs, vents in the wall of said cylinder .adaptedto be covered and uncovered alternately by said piston in its movement from end to end of the cylinder, and a detent yieldingly holding the piston'in either of its extreme positions to permit the accumulation of fluid in one reservoir while the other reservoir is in communication with one of the said vents.

2. A pneumatically operated timing device comprising a cylinder, a dumb-bell piston slidable therein and having spaced heads, a pair of annular grooves formed in one of the heads, a detent extending through,

the Wall of said cylinder and engageable in saidggpooves, alternately, when the piston reaches the ends of its stroke, a spring yieldingly forcing saiddetent into position to engage in said grooves, and a follower for varying the compression of said spring, a

form of invention shown Th1s may obvious-- operated timing devicesource of fluid under pressure, and a pair of reservoirs communicating with such source of supply and with said cylinder at its ends, vents adjacent the ends of said cylinder each of which is'adapted to be opened when the piston is in the opposite end of the cylinder and is retained in such position by said detent, whereby the other vent will be closed by said piston and pressure will accumulate in one of said reservoirs preparatory to returning the piston to the other extremity of its stroke while the other reservoir is being relieved of pressure through the opened vent.

. a piston rod said cylinder and 3. A pneumatically operated timing device comprising a cylinder, a piston reciprocable therein, a source of fluid under pressure, reservoirs communicating with such source of fluid and with said cylinder to act upon the piston and cause its reciprocation, a detent for yieldingly holding the piston in either of its extreme positions of movement, a pipe leading from the source of fluid to said cylinder but closed from communication therewith by said piston in one extreme position of its movement, and a second pipe communicating with said cylinder andwith mechanism t9 beiactuated in time with the reciprocation of said piston, the piston in the other of its extreme positions serving to establish communication between the source of fluid under pressure and said second pipe, together with means for venting said second pipe when such communication is disrupted.

4. A pneumatically operated timing device comprising a source of gas-under pressure, a ported cylinder closed at each end, reciprocable therein of which the central part is thinner than the ends, forming a sliding, ported chamber between said ends and the cylinder walls, said chamber being out of connection with the space between the end of the cylinder and the end of the piston, means for applying gas pressure on opposite ends of the piston for reciprocating it, inlet and outlet means for fluid to and from the said ported chamber, and valve means for regulating the flow of gas to the ends of said piston.

5. A pneumatically operated apparatus for imparting timed reciprocating motion to mechanism, comprising a c linder, arodshaped piston'reciprocable t erein, having a pair of annular grooves formed near one end, a detent extending through the wall of engageablein said grooves, alternately, when the piston reaches the ends of its stroke, a spring yieldingly forcing said detent into position to engage in said grooves, and a follower for varying the compression of said spring, a source of fluid under pressure, and a pair of reservoirs communicating with said source of supply and with said cylinder at its ends, vents ad acent the ends of said cylinder each of WhlCll 1s adapted to be opened when the piston is in the o posite end of the cylinder and is retaine in such position by said detent, whereby the other vent will be closed by. said piston and pressure will accumulate 1n one of said reservoirs preparatory to returning'the piston to the other extremity of its stroke while the other reservoir is being relieved of pressure through the opened vent, means attached to the piston and extending slidably throu h the end of the cylinder, for transferring t e motion of the piston to a mechanism outside the cylinder.

6. A pneumatically operated timing device comprising in combination with a source of fluid under pressure, a ported cylinder in communication therewith, a iston rod, of which the end portions are cylindrical and make a slidin and of which the middle portion is of less thickness than the ends, thereby forming a ported chamber enclosed by the end portions of the rod, and the ported walls of the cylinder, said piston being reciprocable in said cylinder by the pressure of said fluid, means for applying fluid pressure alternately on opposite faces of said pistdn for reciprocating it, valve means for regulating the flow of fluid to said cylinder, and rod means attached. to the piston and extending slidably through the end of the cylinder, for transferring the motion of the piston to a mechanism outside the'cylinder.

7. A pneumatically operated timing device comprising a source of fluid under pres-. sure, a ported cylinder and a piston slidable in said cylinder, pressure reservoirs in constant communication with the source of fluid and with said cylinder at its end portions, vents automatically opened and closed by movement of the piston, whereby when one of said reservoirs is accumulating fluid from said source the other said reservoir is relieved of pressure by the opening of one of the vents, and pressure responsive means for temporarily holding said piston at the ends of said cylinder during building up of suflicient pressure in one reservoir to move the piston to the opposite end of the cylinder.

8. A pneumatically operated timing de vice comprising a ported cylinder, a piston reciprocable in said cylinder, a source of fluid under pressure, reservoirs inconstant communication with said source of fluid and with said cylinder at its end portions, vents automatically opened and closed by movement of the piston to alternately relieve the reservoirs of accumulated pressure, pressure responsive means for temporarily holding said piston at the ends of said cylinder during building up of suflicient pressure in one reservoir to move the piston to the opposite end of the cylinder, and mechfit with the cylinder,

anism actuated by reciprocation of said piston in time with its movements.

9. A pneumatically operated timing device comprising a source of fluid pressure, a ported cylinder, reservolrs in constant communication witheach end of said cylinder and with said source of fluid pressure, valves disposed between said reservoirs and said source of fluid pressure, a piston reciprocal in said cylinder, ternately discharge accumulated fluid from said reservoirs through said cylinder and .time of movement of the piston from the other end of the cylinder, the control means being the valves voirs and the source of fluid pressure.

10. A pneumatically operated timing device comprising a 'source of gas under pressure, a ported cylinder, reservoirs in constant communication with each end of said, cylinder and with said source of gas under pressure, valves disposed between the reservoirs and the source of gas under pressure, a piston reciprocal in the cylinder, the central part of the piston being of less diameter than its ends and forming a sliding chamber between the ends of the piston and the cylinder, the chamber being out of communication with the space between the ends of the cylinder and the ends of the piston, said piston being adapted to alternately connect the reservoirs through said cylinder and said cylinder ports for discharge of accumulated gas therefrom, means .for temporarily holding said pistonin its extreme position during building up of suflicient pressure in one of said reservoirs to move the piston from one end of the cylinder to the other, and pipes connected to said cylinder and adapted for alternate communication with said sliding chamber by movement of said piston, and a single-pipe connected to said cylinder, said pipe being at all times in communication with said sliding chamber.

11. Means for automatically and independently controlling the time of movement of a piston in a cylinder from either of its extreme positions in the cylinder comprising a reservoir for each end of said cylinder, each of said reservoirs being in constant communication with the respective cylinder end to which it is connected and in constant communication through independently adjustable valves with a source of fluid under pressure, ports in said cylinder adapted to be opened by said piston dursaid piston adapted to al-- disposed between the resercylinder, a piston in said inder, and

ing its movement in the cylinder to discharge fluid from thecylinder, and means for yieldingly holding the piston in either of its extreme positions during building up of suflicient pressure in one of said reservoirs to move the treme position.

12. Means for automatically and independently controlling the time of movement of a piston in a cylinder from either of its extreme positions. in the cylinder comprising a reservoir for each end of said cyl-, inder, each of said reservoirs being in constant communication with the respective cylinder end to which it is connected and in constant communication with a source of fluid under pressure, ports in said cylinder adapted to be opened by said piston during its movement in the cylinder to discharge fluid from the cylinder and adjustable means for yieldingly holding the iston in either of its extreme positions dining building up of sufl'icient pressure in one of said reservoirs to move said piston to the other extreme position.

13. A pneumatically vice for piston to the other exthrough a'pipe comprising a pressure operat'ed valve in said pipe, said valve bein connected for pressure operation to a ported cylinder, a source er pressure connected to said cylan exhaust port in said cylinder, said piston being-adapted to alternately connect said pressure operated valve with said source of gas under pressure and with said exhaust port to operate the valve and means for automatically and independently controlling the time of movement of the piston. in the cylinder from either of its extreme positions in the cylinder comprising a reservoir for each end of the cylinder, each of said reservoirs being in constant communication with the respective cylinder end to which it is connected and in constant communication through independently adjustable valves with a source of fluid under pressure, ports in said cylinder adapted to be opened by the piston during. its movement in the cylinder to discharge fluid alternately from said reservoirs and means for yieldingly. holding the iston in either of its extreme positions durlng building up of suflicient pressure in one of said reservoirs to move said piston to the other extreme osition.

14. pneumatically operated timing de vice for controlling the flow of a fluid through a of gas and pipe, said valve being connected for pressure operation to aported cylinder, a piston in said cylinder, a source of gas under pressure connected to said cylinder, and an exhaust port in'said cylinder, said piston being adapted to alternately pipe comprising a pressure opaerated valve 1n said communication with a source of fluid under pressure, ports in said cylinder adapted to be opened by the piston during its movement in the cylinder to discharge fluid from the cylinder and adjustable means for yieldingly holding the iston in either of its extreme positions uring building up of sufficient pressure in one of said reservoirs to move the piston to the other extreme position.

ROY L. CHENAULT. 

